1. Field of the Invention
This invention relates broadly to surgical devices. More particularly, this invention relates to a surgical clip for clamping and/or suturing ducts, vessels, and other tissues, or for anchoring a tissue, or for attaching a foreign body to a tissue.
2. State of the Art
Surgical clips are generally used to apply clamping force to ducts, vessels, and other tissues. In addition, surgical clips are particularly useful in controlling bleeding of a tissue in lieu of suturing or stapling where suturing or stapling is difficult. However, in certain circumstances, the bleeding tissue is lubricous, and applied clips often slip from the tissue and are dislodged, removing the necessary clamping force thereabout. This is particularly a problem when a clip is provided about tissue which is not a conduit of a size which can be completely surrounded by the clip. For example, it is very difficult to secure a clip about a small peripheral portion of ulcerated stomach tissue and therefore it is difficult to effect hemostasis of such bleeding tissue with a clip. Moreover, the problem is amplified when the clip used is very small.
In order to prevent dislodgement, a combination of a clip and a staple has been described in U.S. Pat. No. 5,522,823 to Kuntz et al. In the Kuntz clip, one end portion of the clip is pierced through the tissue and captured in an eye of another end portion of the clip to secure the clip on the tissue. With the clip piercing the tissue, the likelihood that the clip will become inadvertently dislodged is greatly reduced.
While the Kuntz et al. clip represents a step forward, the disclosed clip is not particularly useful in endoscopic procedures. In particular, both the nature of the clip and the manner in which it is applied are complex. For example, in order to facilitate the bending of the clip through various configurations required of its applier, the clip has portions provided with at least four different widths as well as an eye opening. This complex clip structure is not practical for a clip which is to be used in a flexible endoscopy procedure in which the tools used are of very small diameter, e.g., 2-6 mm (0.08-0.24 inch). In addition, for endoscopic procedures it is highly desirable that multiple clips be able to be applied without removing the clip applier from its general location. The Kuntz et al. clip and applier, however, are not particularly adapted for applying multiple clips, as the Kuntz et al. clip does not stack, and the applier with which it is used holds a single clip at a time.
The problems of the Kuntz et al. clip were overcome with the clip described in the parent application hereto. That surgical clip was provided with a generally U-shaped configuration with first and second arms, and a bridge portion therebetween. The first arm was provided with a tip preferably having one or more catches, and the second arm extended into a deformable retainer preferably having a tissue-piercing end and preferably also a hook. During application, the clip was forced over compressed tissue. As the clip was forced over the tissue, the retainer of the second arm was bent and could pierce through the tissue. The retainer was sized to be bent sufficiently toward and around the tip of the first arm so that the hook could engage in one of the catches to secure the clip to the tissue and prevent the clip and tissue from separating. The clip was provided with structure that facilitated the stacking (or chaining) of a plurality of clips in a clip chamber of an applier. The structure included: a notch at a junction of the first arm and the bridge portion adapted to receive the tip of the first arm of another clip; an elongate recess along the exterior of the second arm adapted to receive the retainer of the second arm of another clip; and an interior configuration at the ends of the first and second arms corresponding to an exterior portion of the bridge portion of another clip.
While the clip of the parent application overcame the problems of the prior art, it was found that in certain circumstances, the tip of one arm of the clip did not engage the catch on the other arm. In addition, it was found that to effectively dispense the clip, it was preferable that the clip applier include a mechanism which pulled the penultimate (next) clip proximally after the ultimate clip was dispensed in order to ready the clip applier for use again in firing the next clip. Therefore, it was determined that further improvements to the clip could be made.